Table of Contents
Advertisement
OIL PRIMARY CONTROL LED
DIAGNOSTIC LIGHT
The LED diagnostic light has several functions. It
indicates the state or mode in which the oil burner
is operating. It will also indicate fault conditions,
and help determine cad cell resistance while the
burner is operating.
NORMAL CONDITIONS:
The LED diagnostic light will turn on when the
burner enters the carryover state; the point at
which ignition spark is on, and will remain on
through the run state, where the ignition spark is
terminated but the burner continues to fire.
The LED diagnostic light will turn off at the end of
the burner cycle as the oil primary control enters
the idle state, and will remain off until the next
heating cycle.
FAULT CONDITIONS:
If the LED diagnostic light is flashing quickly; 1 Hz
(½ second on / ½ second off), the oil primary
control is in the lockout state or in restricted mode.
To exit the lockout state, press the reset button.
If the LED diagnostic light is flashing slowly; ¼ Hz
(2 seconds on / 2 seconds off), the oil primary
control is in the recycle state. This indicates that
flame sensing was lost after the lockout timer
expired during the ignition carryover state. The oil
primary control will return to the idle state within 60
seconds.
CAD CELL CONDITION:
If the LED diagnostic light is off, the cad cell is not
sensing flame.
If the LED diagnostic light is on, the cad cell is
sensing flame, or viewing ambient light.
The resistance of the cad cell may be checked
while the oil primary control is in the run state by
pressing the reset button. The LED diagnostic light
will flash the following code:
Table C-2: Cad Cell Resistance
Flashes
Resistance in Ohms
1
Less than 400
2
Between 400 - 800
3
Between 800 – 1600
4
Between 1600 - 5000
Troubleshooting
IMPORTANT: Due to the potential hazard of line
voltage, only a trained, experienced service
technician should perform the troubleshooting
procedure.
PRELIMINARY STEPS:
Check the diagnostic light for indications of burner
condition. Refer to the oil primary control LED
section for details.
LIGHT
WHEN SIMULATING A CALL FOR HEAT AT THE
OIL PRIMARY CONTROL, DISCONNECT AT
LEAST ONE THERMOSTAT LEAD WIRE FROM
THE T1 - T2 TERMINALS TO PREVENT DAMAGE
TO THE THERMOSTAT. NEGLECTING THIS
PROCEDURE MAY BURN OUT THE HEAT
ANTICIPATOR OF A STANDARD 24 VAC
THERMOSTAT, OR CAUSE HARM TO
COMPONENTS WITHIN A MICRO-ELECTRONIC
THERMOSTAT.
Before checking the oil primary control, perform these
preliminary checks, (repair or replace controls as
necessary):
•
Check the power supply; fuse box or breaker, any
service switches, all wiring connections, and burner
motor reset button (if equipped).
•
Check the limit switches to ensure that the switch
contacts are closed.
•
Check the electrode gap and position.
•
Check the contacts between the oil primary control
and the electrodes.
•
Check oil supply (tank gauge).
•
Check the oil nozzle, oil filter, and oil valves.
•
Check the piping or tubing to the oil tank.
•
Check the oil pump pressure.
Check Oil Primary Control and Igniter
If the trouble does not appear to be in the burner or
ignition hardware, check the oil primary control and the
igniter by using the following equipment:
Screwdriver, Voltmeter (0 - 150 V
Insulated jumper wires with both ends stripped.
21
DIAGNOSTIC
)
AC
Hide quick links:
Advertisement
Table of Contents
